In general, when there is a possibility of an article to be damaged due to a load by other goods, an external shock, an internal vibration or the like in the course of loading and transporting goods, the article is protected by inserting a shock-absorbing packaging material between the article and a packaging box. Since such a shock-absorbing packaging material is usually placed to surround the outer surface of the article, an elasticity and a strength are required in addition to a light weight to protect the article.
In recent years, in order to ensure easy processability in conformity with various articles and effectively support a shock transferred from an exterior or the load of an article so as to allow the article to be transported to a destination without being broken, an air cell type shock-absorbing packaging material in which air is filled in a film is being widely used.
FIGS. 1 to 3 are views illustrating a shock-absorbing packaging material according to the conventional art, wherein FIG. 1 is an exploded perspective view illustrating the shock-absorbing packaging material, FIG. 2 is an assembled perspective view of FIG. 1 and FIG. 3 is a view illustrating the shock-absorbing packaging material filled with air.
Referring to FIGS. 1 and 2, a shock-absorbing packaging material 1 according to the conventional art is constructed by an upper outer cover 10 and a lower outer cover 20 which are mutually partially fused to form an air introduction path 16 through which air is introduced from an exterior and which form air cells 15 which communicate with the air introduction path 16 through air guide paths 32 and are filled with air, and an upper inner cover 30 and a lower inner cover 40 which are interposed between the upper outer cover 10 and the lower outer cover 20 to form the air guide paths 32 between the air introduction path 16 and the air cells 15.
That is to say, in the shock-absorbing packaging material 1, the upper and lower inner covers 30 and 40 are inserted between the upper and lower outer covers 10 and 20 to overlap with each other, and the upper outer cover 10, the upper inner cover 30 and the lower inner cover 40 are partially fused at regular intervals in a longitudinal direction to form internal fused portions 31. In this way, the upper outer cover 10 and the upper inner cover 30 are fused to each other, and the air guide paths 32 are formed between the upper inner cover 30 and the lower inner cover 40. Passages which connect the air introduction path 16 and the air guide paths 32 are formed where backing members 41 are disposed at the internal fused portions 31.
After that, longitudinal fused portions 11 are formed at regular intervals by simultaneously fusing the upper and lower outer covers 10 and 20 and the upper and lower inner covers 30 and 40, and the plurality of air cells 15 are formed by finishing through first and second transverse fused portions 12 and 13 at the front and rear ends of the longitudinal fused portions 11. A third transverse fused portion 14 is formed along the front edges of the upper and lower outer covers 10 and 20 forwardly of the first transverse fused portion 12. The third transverse fused portion 14 forms the air introduction path 16 in cooperation with the first transverse fused portion 12.
One end of the air introduction path 16 formed in this way defines an air introduction opening 17 which is open to allow air to be introduced, and the other end of the air introduction path 16 is closed by extending an outermost longitudinal fused portion 11.
In the above-described construction, if an air introduction nozzle is inserted into the air introduction opening 17 of the shock-absorbing packaging material 1 illustrated in FIG. 2 and air is introduced through the air introduction opening 17, air introduced through the air introduction opening 17 is filled in the air cells 15 by passing through the air guide paths 32 via the air introduction path 16. In this way, as illustrated in FIG. 3, the shock-absorbing packaging material 1 in which air is filled in the air cells 15 is completed finally.
Shock-absorbing packaging materials of such a structure are disclosed in Korean Unexamined Patent Publication No. 2009-0105721 entitled “Air bag” and Korean Unexamined Patent Publication No. 2006-0000176 entitled “A packing material which absorbs shock by injected air and a method thereof.” When packaging an article using such a shock-absorbing packaging material, the shock-absorbing packaging material filled with air is disposed to surround the outer surface of the article so as to allow the article to be accommodated in the shock-absorbing packaging material, whereby it is possible to easily protect the article through the shock-absorbing function of air cells.
Further, such a shock-absorbing packaging material may perform not only the function of protecting an article but also the function of keeping a packaged article warm or cold through air cells. Therefore, the shock-absorbing packaging material may be used to package an article which needs to be kept warm or cold.
However, in the case where the conventional shock-absorbing packaging material 1 is used for keeping an article warm or cold, a problem may be caused in that, since heat transfer may easily occur between the inside and the outside of the shock-absorbing packaging material 1 through the longitudinal fused portions 11 formed between the air cells 15, it is difficult to obtain a desired effect of keeping warm or cold.
Furthermore, in the above-described conventional shock-absorbing packaging material 1, when packaging an article, although a shock-absorbing function for the article is provided through the plurality of air cells 15 which are successively formed in a transverse direction, since the air cells 15 are formed in only one layer, shock-absorbency relatively degrades in comparison with a multi-layered air cell structure. Moreover, in the case where an external shock is transferred through a longitudinal fused portion 11 formed between air cells 15, a problem may be caused in that the article is likely to be broken.